A systematic review of three commercial gene expression-based prognostic breast cancer tests has determined that they have potential for improving prognostic and therapeutic prediction. However, more data are needed about the amount of improvement which women will benefit, and how to use the test in decision making about current breast cancer treatment.

The findings were published in the journal Annals of Internal Medicine.

“The introduction of gene expression tests has ushered in a new era in which many conventional clinical markers may be seen merely as surrogates for more fundamental genetic and physiologic processes that can be measured with these tests,” write the authors.

“The multidimensional nature of these predictors demands that large numbers of clinically homogeneous patients to be used in the validation process and that exceptional rigor and discipline be applied in evaluation. Every study provides an opportunity to modify a genetic signature, but we must find the right balance between speed of innovation and development of reliable tools.”

SOURCES:
Annals of Internal Medicine, March 18, 2008, published online February 5, 2008
American College of Physicians (http://www.acponline.org)